What Are The Different Types Of Pins?

Pin fasteners are an extremely versatile type of fastener that are used by DIYers at home as well as experts in the engineering and mechanical industries. With so many different types of pins out there, it can be easy to confuse one type with another or to be unsure which type of pin you need for your project. This detailed guide aims to provide a comprehensive overview of pins, their unique properties, and the applications for which they are most often used.

Different Types of Pins:

PIN TYPE	IMAGE	DESIGN & FUNCTION	APPLICATIONS	COMMON FINISHES
Split Pins		Also known as cotter pins, these pins are manufactured from heavy wire that is bent in half and features a semi-circular section at the top.	Used to hold fasteners such as nuts in position by hammering them through the hole of the fastener and bending the legs, usually in engineering applications	Steel, Brass, Self Colour
Dowel Pins		A small solid tube available in a wide variety of diameters in metric and imperial measurements.	Dowel pins are a very common type of fastener, you'll often see wooden dowels come alongside flat-pack furniture to help hold the pieces together. Metal dowels however are used in the production of machinery and industrial equipment.	Wood, Steel, Self Colour, Black
Roll Pins		A hollowed-out metal tube that is chamfered or rounded at both ends.	Roll pins are most commonly used to hold two components together through pressure, which is created by the outside walls expanding to fill the hole it is inserted into.	Steel, Self Colour, Zinc plated
Spirol Pins		A coiled-up piece of sheet metal in the shape of a tube.	Similarly to spring pins, these pins are designed to hold two components together by exerting pressure from their outside walls. They are generally regarded as being stronger than roll pins.	Steel, Self Colour, Zinc Plated
Taper Pins		A solid metal tube where one end has a larger diameter than the other.	These pins are tapped into place using a hammer in order to lock components of machines in place. They're commonly used in gearboxes and printing presses.	Self Colour, Zinc Plated
R Pins		Also known as R clips, these pins are manufactured from hard wire and are shaped like the letter "R".	Used to secure shafts and axles into position by guiding the straight leg of the pin into the hole of the shaft. The waved leg of the clip then rests on the outside of the shaft and the sealed gap between the legs holds the clip in position.	Zinc Plated
Clevis Pins		A metal cylinder with a round head at one end and a hole through the shank at the other end.	Clevis pins are inserted through holes in machine or vehicle components such as shackles, clevis jaws and lifting equipment. They are often used alongside a split pin, which is put through the hole in the shank after installation to keep it secure.	Steel, Zinc Plated
Lynch Pins		A solid metal tube with a hexagonal head that has a ring passing through it.	The pin is fed through a hole at the end of a shaft or axle before the ring is snapped down to ensure a secure fit. They can be used in heavy-duty applications such as on agricultural machinery. Linch pins can also be used to replace a broken padlock temporarily.	Steel, Zinc Plated, Yellow Passivated, Brass
Detent Pins		Detent pins are much like dowels in their designs, with the addition of a ring fed through a hole at one end and a detent at the other, hence their name.	These pins are inserted into holes to help hold components together and are a strength upgrade compared to dowels since they feature a spring-loaded ball bearing that gives the pin a self-locking ability. The ring on the other end can be used to remove the pins more easily than other types, with simply a sharp tug, hence the reason they are also referred to as quick-release pins. For this reason, they are often used in applications where disassembly and reassembly are frequent.	Steel, Zinc Plated
Grooved Pins		Again, groove pins are similar to dowel pins in their profile, however, they feature shallow grooves that run down the length of the pin.	Thanks to their grooves, these pins boast extra shock and vibration absorption in applications where they are used to hold components together.	Steel, Zinc Plated
Wire Lock Pins		A solid metal cylinder with a larger diameter head and a curved metal wire that is attached at the head end.	These steel pins most commonly used to add or remove accessories on machines and equipment. The accessory is fed onto the curved wire and the loop end of the wire is then pulled over the edge of the pin to secure it in place.	Steel, Zinc Plated

Common Materials Used in Pin Manufacturing

Stainless steel: used on a huge variety of fixings and fasteners due to its high strength as well as its rust and corrosion resistance properties. The two most common types of stainless steel are A2 and A4, check out our guide on the difference between a2 and a4 stainless steel for more information.
Carbon steel: an environmentally friendly option due to its ease of recycling, carbon steel is easy to weld and machine to make it fit a wide variety of applications. Whilst it does share the same resisting properties as stainless steel, carbon steel can be painted with protective materials.
Zinc: many pins are coated in zinc to create an added layer of resistance to the elements and to prevent moisture from reaching the base metal of the fastener.
Brass: another coating option is brass, which is an alloy of zinc and copper. It has anti-corrosion properties but the brass finish also serves as a decorative element.

What Industries Are Pin Fasteners Used In?

As previously mentioned, pins are not only used by DIYers, but also by professional engineers and mechanics. Some of the industries they are most commonly used in are:

The automotive industry: many of the pin types mentioned in this article are used in the production of vehicles. Taper pins are used in the creation of gearboxes since they can stop components from twisting and spring pins are used to secure bearings, bushings and shafts. You can learn more about this in our article: What are spring pins used for?
Aerospace and aviation: dowel pins are used to secure control surfaces to aircraft as well as to join structural components.
Industrial machinery and equipment: almost all of the various types of pins in the table above are used in machinery. Dowel pins are used to align machine parts to ensure accuracy and precision, spring pins are used to fix parts of a machine together and lynch pins stop components from sliding off of shafts and axles.
DIY projects: there are well-known uses for pin fasteners in DIY applications such as wooden dowels being used when building flat-packed furniture, but there are more creative uses that can easily be achieved without professional knowledge or tools such as using a lynch pin as a replacement tool box lock or using spring pins for creating functional closures for boxes.

For more information on pins, check out our other articles such as how to use dowel pins or feel free to get in contact with us.

How to Use Dowel Pins